British Columbia

New UVic research into physical markers of stress among nurses finds disrupted sleep patterns

Stress over a long period of time can take a physical toll. New research from the University of Victoria is looking at what effect stress is having on front-line nurses.

Preliminary results show nurses sleep less and more lightly

Researchers at the University of Victoria had nurses wear monitors on and off shift to track changes in their heart rates. (Apu Gomes/AFP/Getty Images)

New research from the University of Victoria looking at the physiological impacts of stress on nurses shows that many have disrupted sleep patterns and other markers of stress. 

The study, funded by UVic's Centre for Occupational Research and Testing, is being spearheaded by graduate student Marisa Harrington and her supervisor Lynneth Stuart-Hill, an occupational physiologist and associate professor at UVic.

In it, 10 Victoria-area hospital nurses wore a watch-sized monitor and chest strap heart-rate monitor during an eight-day shift rotation where they worked four days on, including two day shifts and two night shifts, and four days off. They also contributed saliva samples during the testing period. 

Harrington remotely recorded nurses' sleeping patterns, heart rate variability and biomarkers within their saliva including levels of melatonin which plays a role in sleep-wake cycles, the stress hormone cortisol and interleukin-6 which affects inflammation.

Harrington said while the results are preliminary, there are clear trends around sleep and heart rate variability. 

Nursing is even more stressful during the pandemic, researchers say. (Mikaela MacKenzie/The Canadian Press)

Compared to the average adult who has light sleep, deep sleep and rapid eye movement or REM sleep, nurses were spending a lot more time in light sleep and less time in deeper REM sleep, she said.

"We've seen heightened activation of the sympathetic system, or the fight-or-flight response. Even lasting into [their] days off. These are nurses that aren't on shift. They are in day three of their four days off, and they're still having this heightened cardiovascular stress response even when they're not on shift," said Harrington.

Harrington says this physiological toll could have longer-term impacts, including increasing the potential for stroke, diabetes and hypertension.

This study fits into broader research into the stress responses of shift workers. Harrington says much of the research in this field focused on male-dominated professions like military, policing, firefighting, search and rescue, but not into the profession nursing. 

The COVID-19 pandemic also adds an additional layer of complexity.

"Before the pandemic, there was tons of evidence that nursing was a stressful profession. And working during the pandemic has only exacerbated that," Harrington said. "There's always a potential down the road, say once this pandemic ends, to do the same type of measurement again and see if the responses are similar in a COVID world and in a post-COVID world."

Harrington will continue with a new round of study subjects in the coming months, with most of the research set to conclude this spring.

Listen to the segment on CBC's All Points West:

With files from All Points West